2008 tahoe.5.3l, this truck will cause me to turning into a alcoholic. The lifters got chewed up, brought to a friend cause I didn't have time to do it. He decided to do the afm delete on it, didn't ask, and now it's been a straight nightmare. He didn't know the truck needed to be tuned properly so this to work correctly. I went through my brother and got a used ecu tuned to my vin# with the afm deleted from it. Got everything back together now I can not get rid of the p0300. You can hear the timing is not right in the truck. Does the vvt have to be turned off aswell in order for it to run correctly? Now the guy i got the ecu from said i might need the crank position sensor relearned. I told my friend that did the work that and he said he attempted it 5 times but he's not sure if he worked cause it never came up with a message stating it was complete. So could it either be the vvt needs to be disabled or that the crank position sensor needs to be relearned? O2 sensors were also changed, maf sensored was changed, new plugs and wires, new map sensor. Bunch of new stuff.
2008 tahoe 5.3l afm/dod delete issue
- Thread starter Nickct203
- Start date
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yes, as I understand it. if your truck had vvt and your new cam isn't vvt you will need to disable that along with the afm. I don't know if that's your code thou. I feel like it might have been better to tune afm/vvt off in your original ecm, than get another that didn't come with afm. you might have a total difference engine calibration in that ecm. since it probably came from a different year truck, if all they did was change vin.
you can mail the ecm off for like 50$ to have it turned off in your original ecm. or hp tuners will do it if you know someone with it. it's 2 credits to unlock it then it's 2 drop down boxes.
you can mail the ecm off for like 50$ to have it turned off in your original ecm. or hp tuners will do it if you know someone with it. it's 2 credits to unlock it then it's 2 drop down boxes.
Yea all the tuner asked was for the year make model vin and what I needed done. I forgot to have the vvt turned off as well.
Yea I'm not sure. That's the only thing I could think of on why the timing could be off and possibly why the crank position sensor can't be set. This is what's driving me nuts. Fix 1 thing it'll trigger something else. Sunday after I put the ecu in it seemed to idle great. You can hear a small timing miss but idle great. My friend put 4 new oxygen sensors in and it just all went to hell again. P0300 plus the trac control is going haywire cause of how hard it's shuttering.
Dustin Jackson
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I would get all the facts straight so that we are working with good information, like what parts he used and if you engine even has VVT.
Verifying the timing chain is installed right isn't too hard but you might need to do that and go back through your motor yourself to see if everything is done right.
Verifying the timing chain is installed right isn't too hard but you might need to do that and go back through your motor yourself to see if everything is done right.
A non-vvt cam was installed, and I never had the vvt turned off in the ecu.
iamdub
Full Access Member
I always thought VVT was introduced for these for the '09+ models.
I found somethings online that say it started in 2007, other articles say it started in 2010.
A little more info from me trying to figure stuff. I put my small little scanner on the truck and started looking if the O2 sensors were working right. The front O2 sensors(B1S1 and B2S1)were registering values, but the back O2 sensors(B1S2 and B2S2) were not registering anything all zeros.
